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The performance of vertical-cavity surface-emitting lasers (VCSELs) is strongly dependent on the spectral detuning between the gain peak and the resonance wavelength. Here, we use angle-resolved photoluminescence spectroscopy to investigate the emission properties of AlGaN-based VCSELs emitting in the ultraviolet-B spectral range with different detuning between the photoluminescence peak of the quantum-wells and the resonance wavelength. Accurate setting of the cavity length, and thereby the resonance wavelength, is accomplished by using doping-selective electrochemical etching of AlGaN sacrificial layers for substrate removal combined with deposition of dielectric spacer layers. By matching the resonance wavelength to the quantum-wells photoluminescence peak, a threshold power density of 0.4 MW/cm2 was achieved, and this was possible only for smooth etched surfaces with a root mean square roughness below 2 nm. These results demonstrate the importance of accurate cavity length control and surface smoothness to achieve low-threshold AlGaN-based ultraviolet VCSELs. [ABSTRACT FROM AUTHOR]

One of the most common causes of accidents in food industry buildings is slipping caused, in particular, by the spilling of liquid substances on the floor, which reduces the coefficient of friction between floor and sole. The aim of this study was to assess the performance of the most common types of flooring used in the food industry, where, owing to the characteristics of the manufacturing stages, the probability of liquid spilling is higher. Five different types of flooring, usually utilized in the food industry, were tested: two unglazed gres tiles and three resin floors. The tiles were different in surface shape: one was flat (gres A), the other was a tile with embossed surface (gres B). The surface of the resin used was made up of a three-component polyurethane/cement-based mortar (resin A), a two-component epoxy (resin B) and a two-component epoxy in water dispersion (resin C). To classify a surface as anti-slip the Dynamic Friction Coefficient (DFC) was measured in five different conditions (dry, wet with distilled water, contaminated by olive oil, cow's milk and red wine) and with three types of sliders (leather only for dry condition, rubber and synthetic for contaminated conditions) for each floor panel. The analysis of ANOVA showed that the slipping properties of the floors did not depend only on surface roughness but also on the chemical characteristics of the surfaces in contact with each other (sole surface/floor). [ABSTRACT FROM AUTHOR]

Strains of Lactobacillus plantarum were grown and stored in cherry (ChJ), pineapple (PJ), carrot (CJ), and tomato (TJ) juices to mimic the chemical composition of the respective matrices. Wheat flour hydrolysate (WFH), whey milk (W), and MRS broth were also used as representatives of other ecosystems. The growth rates and cell densities of L. plantarum strains during fermentation (24 h at 30°C) and storage (21 days at 4/C) differed only in part, being mainly influenced by the matrix. ChJ and PJ were the most stressful juices for growth and survival. Overall, the growth in juices was negatively correlated with the initial concentration of malic acid and carbohydrates. The consumption of malic acid was noticeable for all juices, but mainly during fermentation and storage of ChJ. Decreases of branched-chain amino acids (BCAA)—with the concomitant increase of their respective branched alcohols—and His and increases of Glu and gamma-aminobutyric acid (GABA) were the main traits of the catabolism of free amino acids (FAA), which were mainly evident under less acidic conditions (CJ and TJ). The increase of Tyr was found only during storage of ChJ. Some aldehydes (e.g., 3-methyl-butanal) were reduced to the corresponding alcohols (e.g., 3-methyl-1-butanol). After both fermentation and storage, acetic acid increased in all fermented juices, which implied the activation of the acetate kinase route. Diacetyl was the ketone found at the highest level, and butyric acid increased in almost all fermented juices. Data were processed through multidimensional statistical analyses. Except for CJ, the juices (mainly ChJ) seemed to induce specific metabolic traits, which differed in part among the strains. This study provided more in-depth knowledge on the metabolic mechanisms of growth and maintenance of L. plantarum in vegetable and fruit habitats, which also provided helpful information to select the most suitable starters for fermentation of targeted matrices. [ABSTRACT FROM AUTHOR]

Psoriasis is a chronic inflammatory skin disease, characterized by an enhanced proliferation and a deregulated differentiation of keratinocytes. hMena is an actin regulatory protein involved in the control of cell motility and adhesion. hMena results up-modulated in several human tumors with respect to normal tissues and its expression has been positively correlated to proliferation rate, tumor size and aggressiveness in response to mitogenic stimuli, such as epidermal growth factor. The hyperproliferation of keratinocytes observed in psoriasis prompted us to evaluate hMena expression on biopsies collected from involved and uninvolved skin of 12 patients with active plaque-type psoriasis with respect to healthy skin. We analyzed the expression of hMena at transcript and protein levels by quantitative RT-PCR and immunohistochemistry. We correlated the expression of hMena to Ki67 proliferation index and to keratin 10 (K10) and keratin 16 (K16) used as markers of keratinocyte differentiation and activation. We demonstrated the expression of hMena in a hyperproliferative skin condition not related to neoplastic transformation. Interestingly, we observed that hMena is not expressed in healthy skin, but it becomes detectable in non-lesional areas and it is even more expressed in lesional psoriatic skin. In addition, we found that hMena expression is correlated to the rate of keratinocyte proliferation and activation. Hence, our observations indicate hMena as a new possible player, involved in the development and/or maintenance of the hyperproliferative state of psoriatic keratinocytes. [ABSTRACT FROM AUTHOR]

Cutaneous pigmentation is regulated by a complex melanogenic network in which both keratinocytes and fibroblasts synthesize growth factors and cytokines. Solar lentigo (SL) is characterized by hyperpigmented lesions occurring on photodamaged skin areas. Despite the association of SL to ultraviolet (UV) exposure, the mechanisms underlying the development of these spots are not completely defined. To analyse the involvement of the fibroblast-derived growth factors, hepatocyte growth factor (HGF), keratinocyte growth factor (KGF) and stem cell factor (SCF) in SL hyperpigmentation; to evaluate whether the photoageing process occurring in fibroblasts could be responsible for the altered expression of these cytokines; and to investigate a new possible role of KGF in regulating pigmentation through the specific induction of melanogenic cytokines by keratinocytes. We performed immunohistochemical analysis of HGF, KGF and SCF on SL biopsies. We analysed the mRNA expression of these cytokines using an in vitro model of photoageing induced on fibroblasts. Finally, we evaluated the effects of KGF on the expression of melanogenic cytokines at the mRNA and protein levels on keratinocytes. We found positive staining for HGF, KGF and SCF in the upper dermis of SL lesions and a significant induction of the three cytokines in photoaged fibroblasts. We also demonstrated the contribution of KGF to pigmentation, showing its ability specifically to modulate the expression of SCF in keratinocytes. Fibroblasts may be persistently activated by UV exposure to release melanogenic growth factors; this inducible cytokine network acts both directly and indirectly through keratinocytes and may contribute to the hyperpigmentation of SL. [ABSTRACT FROM AUTHOR]

The article describes the case of a 60-year-old man with heterozygous familial hypercholesterolemia who experienced anaphylactic-like reaction between low-density lipoprotein (LDL) apheresis procedure and intake of crafted or home-made white wine. Topics discussed include the patient's medical history, diagnostic examinations performed on the patient, and side effects associated with LDL apheresis. The study shows how a careful medical history can help understand reactions during LDL apheresis.

The nuclear receptor peroxisome proliferator-activated receptor gamma (PPARγ) controls the expression of genes involved in the regulation of lipid and glucose metabolism, cell proliferation/differentiation as well as inflammatory pathways. Pivotal studies in human sebocytes and isolated sebaceous glands have raised the interesting possibility that compounds acting on PPARγ can modulate sebaceous lipids and inflammation and, as such, may be useful in the treatment of acne. To investigate the role of this receptor in the regulation of lipid synthesis, proliferation and inflammation, we used the SZ95 sebaceous gland cell line stimulated with insulin. In sebocytes, insulin signaling activated the phosphatidylinositide 3-kinase-Akt (PI3K/Akt) and mammalian target of rapamycin (mTOR) pathways, which, in turn, induced high protein/lipid synthesis, increased cell growth and proliferation as well as inflammation. As regards lipogenesis, insulin initially stimulated the formation of unsaturated lipids and then the neosynthesis of lipids. The results showed, that the modulation of PPARγ, counteracted the insulin-induced altered lipogenesis, evident through a decrease in gene expression of key enzymes responsible for the synthesis of fatty acids, and through a reduction of lipid species synthesis analyzed by Oil/Nile Red staining and GC–MS. PPARγ modulation also regulated the insulin-induced proliferation, inhibiting the cell cycle progression and p21WAF1/CIP1 (p21) protein reduction. Moreover, the expression of inflammatory cytokines, induced by insulin or lipopolysaccharide (LPS), was down-modulated. In PPARγ-deficient cells or in the presence of GW9662 antagonist, all these observed effects were abolished, indicating that PPARγ activation plays a role in regulating alteration of lipogenesis, cell proliferation and inflammatory signaling. We demonstrated that selective modulation of PPARγ activity is likely to represent a therapeutic strategy for the treatment of acne. [ABSTRACT FROM AUTHOR]

Background Dermatitis herpetiformis (DH), the skin's expression of coeliac disease (CD), is induced by the presence of IgA antibodies and epidermal transglutaminase (TG3) as the main autoantigen, stored in the papillary dermis and on the vessel walls. Aims To evaluate the presence of IgA and TG3 deposits, considered to be the first step in inducing DH, in healthy skin of coeliac patients without cutaneous manifestations. Methods Punch biopsies were taken from 11 consecutive coeliac patients, two with DH and nine without cutaneous manifestations, three of whom were adhering to a gluten-free diet (GFD), and evaluated for the presence of deposits in the upper dermis and vessel walls by immunofluorescence and confocal microscopy. Results In coeliac patients affected by DH we found the presence of IgA and TG3 deposits mainly on the upper dermis, but also in vessel walls. In all coeliac patients without DH and also in those patients who were following a strict GFD, we found widely variable deposits of IgA and TG3 in both the papillary dermis and the vessel walls, although a lower intensity of the fluorescence signal was detected than with coeliac patients affected by DH. Double immunostaining with anti-IgA and anti-TG3 antibodies showed a strong co-localization in the upper dermis in patients with DH and a weaker co-localization in those without DH. Conclusions We have demonstrated the presence of IgA and TG3 deposits in the healthy skin of coeliac patients, which are considered to play a central role in the pathogenesis of DH. [ABSTRACT FROM AUTHOR]

Kovacs D, Falchi M, Cardinali G, Raffa S, Carducci M, Cota C, Amantea A, Torrisi MR, Picardo M. Immunohistochemical analysis of keratinocyte growth factor and fibroblast growth factor 10 expression in psoriasis.The pathogenic mechanism underlying the hyperproliferation of keratinocytes in psoriasis is still not completely clarified. The production of cytokines released by activated T lymphocytes infiltrating the upper dermis probably has a crucial role. Even dermal fibroblasts can participate in the process through the secretion of growth factors, and some studies have reported an increased expression of the insulin-like growth factor 1. Few studies, however, have focused on the possible involvement of the keratinocyte growth factor (KGF/FGF-7) and the fibroblast growth factor 10 (FGF-10/KGF-2), which are secreted by fibroblasts and stimulate keratinocyte proliferation acting through a receptor specifically expressed by epithelial cells. The aim of this study was to investigate the expression of KGF and FGF-10 on the skin of patients with psoriasis by immunohistochemical analysis and to evaluate the correlation with the lymphocyte infiltrate and the epidermal proliferation. Immunostaining for KGF and FGF-10 showed that both the growth factors are upregulated in the upper dermis of psoriatic skin, and that the expression is correlated with the presence of T-cell infiltrate and with keratinocyte proliferation. Our data suggest that in psoriatic lesions activated lymphocytes can stimulate fibroblasts to produce KGF and FGF-10, which in turn contribute to sustain the hyperproliferative status of the keratinocytes. [ABSTRACT FROM AUTHOR]

Mechanical mapping with chemical specificity of biological samples is now made possible by joint micro-Brillouin and micro-Raman measurements. In this work, thanks to the unprecedented contrast of a new tandem Fabry-Perot interferometer, we demonstrate simultaneous detection of Brillouin and Raman spectra from different Candida biofilms. Our proof-of-concept study reveals the potential of this label-free joint micro-spectroscopy technique in challenging microbiological issues. In particular, heterogeneous chemo-mechanical maps of Candida biofilms are obtained, without the need for staining or touching the sample. The correlative Raman and Brillouin investigation evidences the role of both extracellular polymeric substances and of hydration water in inducing a marked local softening of the biofilm. [ABSTRACT FROM AUTHOR]

Summary Isolated angiokeratomas are common benign cutaneous lesions, generally deemed unworthy of further investigation. In contrast, diffuse angiokeratomas should alert the physician to a possible diagnosis of Fabry disease, a rare X-linked lysosomal storage disorder, characterized by α-galactosidase deficiency. Glycosphingolipids accumulate in cells throughout the body resulting in progressive multi-organ failure. Difficulties are encountered when trying to interpret the significance of angiokeratomas because they may also occur in other lysosomal storage disorders and rarely in an isolated manner in Fabry disease. We present an algorithm for the classification of angiokeratomas which might prove useful for the diagnosis and management of Fabry disease. Assessment of the clinical features and location of the lesions, personal and family history, skin biopsy, dermoscopy and electron microscopy imaging are sequential steps in the diagnostic process. Assessing the deficiency of α-galactosidase enzyme activity is essential to confirm the diagnosis in males, while mutation analysis is always needed in females. Potentially this algorithm can change the current approach to patients when Fabry disease is suspected, thus improving the diagnostic strategy and management of this disorder. It remains to be decided whether the use of an algorithm might reduce the number of genetic consultations. As evidence has shown the efficacy of enzyme replacement therapy in halting progression of the disease before the onset of irreversible organ damage, it is advisable to aim at an early diagnosis in order to achieve timely initiation of effective treatment with benefits for patients and appropriate use of medical resources. [ABSTRACT FROM AUTHOR]

Here, we investigated the role of telomerase on Bcl-2-dependent apoptosis. To this end, the 4625 Bcl-2/Bcl-xL bispecific antisense oligonucleotide and the HA14-1 Bcl-2 inhibitor were used. We found that apoptosis induced by 4625 oligonucleotide was associated with decreased Bcl-2 protein expression and telomerase activity, while HA14-1 triggered apoptosis without affecting both Bcl-2 and telomerase levels. Interestingly, HA14-1 treatment resulted in a profound change from predominantly nuclear to a predominantly cytoplasmic localization of hTERT. Downregulation of endogenous hTERT protein by RNA interference markedly increased apoptosis induced by both 4625 and HA14-1, while overexpression of wild-type hTERT blocked Bcl-2-dependent apoptosis in a p53-independent manner. Catalytically and biologically inactive hTERT mutants showed a similar behavior as the wild-type form, indicating that hTERT inhibited the 4625 and HA14-1-induced apoptosis regardless of telomerase activity and its ability to lengthening telomeres. Finally, hTERT overexpression abrogated 4625 and HA14-1-induced mitochondrial dysfunction and nuclear translocation of hTERT. In conclusion, our results demonstrate that hTERT is involved in mitochondrial apoptosis induced by targeted inhibition of Bcl-2.Cell Death and Differentiation (2005) 12, 1429–1438. doi:10.1038/sj.cdd.4401670; published online 27 May 2005 [ABSTRACT FROM AUTHOR]

l. corte, m. lattanzi, p. buzzini, a. bolano, f. fatichenti and g. cardinali. 2005. Two different strain characterization techniques, random amplified polymorphic DNA (RAPD) and killer toxin sensitivity (KTS), were compared to assess their typing performance using a set of 30 certified Saccharomyces cerevisiae strains. A sequential random resampling procedure was employed to subdivide the 32 descriptors in eight sets, in order to compare the differential performances of the two techniques with diverse number of characters. Results showed that RAPD performs better than killer, although the complete differentiation of the strains under study could be obtained only by combining profiles from the two techniques The combination of different typing techniques was useful when discriminating similar organisms. In such cases, the introduction of a second typing technique can be more advantageous than increasing the number of characters obtained with a single method. The distribution of among-strains pairwise distances and the relative performance of the two techniques has implications for the study of biodiversity, taxonomy and microbial ecology. [ABSTRACT FROM AUTHOR]